In a world where many patients are still afraid they will be left looking ‘overdone’ and ‘unable to move their face’ after treatment with botulinum neurotoxin type A (BoNTA), it is perhaps reasonable to suggest that many patients are largely unaware of the vast majority of cosmetic uses that this drug has—let alone the number of therapeutic uses. A 2017 TIME Magazine headline, ‘How Botox became the drug the that's treating everything’, supports the notion that between approved and off-label uses, BoNTA really is ‘a marvel of medicine’ (Sifferlin, 2017).
It is perhaps one thing expecting patients to understand the options available to them when they approach their chosen practitioner for treatment, but it is also worth noting that a significant number of healthcare professionals using BoNTA on a daily basis may be largely unaware of the nature of this procedure—and the results it offers in reality. This article aims to highlight indications for treatment of bruxism using BoNTA to healthcare professionals practising medical aesthetics. This article will also attempt to provide basic guidance on how important a sound understanding of suitable candidates for this procedure are, and what alternative views must be considered when thinking about delivering this treatment.
BoNTA: behind the scenes
It is well known that the cosmetic industry is booming in the UK. Reported to have been worth £2.3 billion in 2010, and estimated to rise to £3.6 billion by 2015, it is fair to assume that more recent figures will show a further increase in popularity (Department of Health and Social Care (DHSC), 2013). BoNTA is part of a group of non-surgical treatments that account for 90% of all cosmetic procedures in the UK and 75% of the market value (DHSC, 2013). With these figures in mind, it is reasonable to suggest that BoNTA is a widely used and relatively well tolerated procedure; although it is important to be aware that there are no centralised and comprehensive data on the scale of adverse health complications associated with such treatments (Houses of Parliament, 2013). Despite its rising popularity and multiple uses, how educated are we on the mode of action for this popular medicine?
Nigam and Nigam (2010) stated that BoNTA is a neurotoxin produced by the bacterium clostridium botulinum—one of the most poisonous biological substances known to man. BoNTA is able to work by interfering and blocking the release of acetylcholine (the main neurotransmitter at the neuromuscular junction), thus causing muscle paralysis. Put simply, the neurotoxin acts directly on motor neurons (nerve cells that that originate in the spinal cord and synapse with muscle fibres to facilitate muscle contraction) in order to reduce muscle activity (Nigam and Nigam, 2010; Allergan, 2019). This means that when injected cosmetically or therapeutically, the neurotoxin works directly on the muscle being injected to reduce muscle activity.
Away from the headlines, it is important for clinicians to have an awareness that neurotoxin produced by clostridium botulinum can have an extremely harmful impact on humans when introduced in the wrong circumstances. Ingestion of BoNTA leads to a clinical syndrome characterised by cranial nerve palsies, oculobulbar weakness and symmetrical flaccid paralysis in the absence of fever—known as botulism (Nield, 2019). The World Health Organization (WHO) provide detailed information on the different types of Botulism, as well as the various differences in exposure and transmission. However, WHO (2018) also stated that, although this is the same bacterium that is used to produce BoNTA, such cosmetic and clinical treatments employ the ‘purified and heavily diluted botulinum neurotoxin type A. Treatment is administered in the medical setting, tailored according to the needs of the patient and is usually well tolerated—although occasional side effects are observed’ (WHO, 2018).
Bruxism: the basics
Bruxism is the term used to describe teeth grinding and jaw clenching. Colgate recently shared figures which stated that this condition affects approximately 30 to 40 million children and adults in the US (Mool, 2019). Although the exact cause of bruxism is not clear, many papers suggest that it is linked to factors such as stress, anxiety, sleep disorders, certain medications and, sometimes, lifestyle factors (NHS, 2017a). The Bruxism Association (2019) commented that nearly 70% of bruxism cases are caused by stress and/or anxiety. With this figure in mind, it is likely that many medical practitioners have previously been, or soon will be, asked about the potential for injectable treatment related to this condition. Sufferers of this complaint experience symptoms such as headaches, temporomandibular joint (TMJ) discomfort, facial myalgia, ear ache, chronic sleep disruption and, potentially, diminished tooth enamel, sensitivity and chipped teeth (The Bruxism Association, 2019; Mool, 2019). Considering the impact on patient quality of life, it quickly becomes evident why a patient who has bruxism would want to explore all available treatment options.
It is the author's belief that, when taking a holistic view of a patient, especially during a consultation for facial treatment, it is vital that treating practitioners are aware of the symptoms of bruxism. This is not only to ensure that the patient can be supported to explore the range of available treatment options, but also so that it can be ensured that no ongoing side-effects of the condition will interfere with aesthetic treatment outcomes. Symptoms such as long-term facial pain and potentially facial swelling on the side of the lower jaw (caused by clenching) (Mool, 2019) can be mistaken for an adverse event post-procedure if the cause of the swelling has not been explicitly highlighted and/or discussed (and potentially prioritised for treatment) during the consultation.
Treatment options
Yiannakopoulou (2015) reported on the therapeutic and cosmetic use of BoNTA, highlighting that the drug has been used therapeutically for almost two centuries. Despite this, it is not, and should not be, the first line of treatment for any patient who is experiencing bruxism.
Other treatment options include a mouth guard/mouth splint, muscle relaxation exercises, employment of sleep hygiene techniques (nocturnal bruxism), cognitive-behavioural therapy (CBT) and changes to certain lifestyle factors (NHS, 2017b). The author believes it is also imperative to ensure that regular dental reviews take place, to ensure that any problems caused as a result of bruxism can be treated as soon as possible in order to prevent further damage.
It is also worth noting that underlying dental problems can exacerbate delayed-onset complications in cases where a dermal filler treatment has taken place when there is an undiagnosed localised infection, or where dental treatment has recently occurred (De Boulle and Heydenrych, 2015). Once again, it is reasonable to emphasise the requirement for in-depth assessment and consultation prior to treatment. Typically, a patient may not associate any cosmetic treatment as something that could interact with an ongoing medical/dental problem (despite the procedure being carried out by a medical professional). Thus, it is the responsibility of the injecting practitioner to fully question and consult the patient, making them aware of any possible eventualities.
For patients who do present with concerns regarding Bruxism, the consultation also provides an opportunity for the consulting practitioner to employ a holistic approach and individual consideration of which treatment options are most viable for that particular patient. There are some things to consider when consulting with a patient who has bruxism.
First, is there a need to begin an ongoing treatment plan, treating bruxism with BoNTA, if the patient would achieve the same success by making some relatively simple lifestyle changes? Cutting back on alcohol and stopping smoking can both help prevent/reduce teeth grinding. Depending on the severity of the problem, this may be all a particular patient needs to do to resolve the issue (NHS, 2017b).
Second, if the patient has disclosed ongoing mental health problems, such as stress and anxiety, is it fair to assume that they are being treated for this? If the practitioner assumes that this is the case and treats the patient using BoNTA, and the bruxism continues, due in part to ongoing psychological issues, then it is fair to say that the patient has not been considered holistically. This is not to say that all treating practitioners must be able to provide support of all varieties; it is a reminder that practitioners must adopt an individual approach and be able to signpost and advise patients regarding other treatment options. Another example might be that a patient presents for bruxism treatment without consulting their dentist first—perhaps due to an ongoing fear or phobia. Should treatment for bruxism using BoNTA occur without this being highlighted and addressed, it could be argued that this lacks holistic oversight and could be regarded as unethical. A simple, more cost-effective option, such as a mouthguard or mouth-splint, could have been tried first.
Botox and bruxism
Based on the mode of action of BoNTA, we know that when injected into the correct muscle/muscles, we can attempt to weaken the area enough to prevent involuntary grinding of the teeth and clenching of the jaw. Although treating the masseter alone may not always completely reduce or prevent bruxism or its side effects, when injecting a dose that is able to weaken the masseter enough to prevent symptoms of bruxism, the patient must be made aware that there may be a reduced ability to chew certain foods, such as well-cooked meat or crusty bread. This procedure differs from the treatment used for facial slimming, whereby the same muscles may be treated with a much lower dose of BoNTA, with the intention to simply to weaken the bulk of the masseter muscle and not completely prevent muscle action.
With this in mind, it is reasonable to suggest that the successful treatment of bruxism using BoNTA not only requires specialist training in relation to injection placement and dosage, but also a degree of clinical judgement and the ability to assess the patient's severity of bruxism, and how symptoms may be reduced with proper injection technique and dosage of product.
Several papers report the use of variable doses of BoNTA for effective results when treating bruxism. The study of Tan and Jankovic (2000) included the use of 25–100 units per masseter, per treatment. Conversely, Talakoub and Wesley (2018) used a standard 50 units per masseter, per treatment, but also highlighted that in some cases, treatment of the temporalis was also required. This supports the notion that treating the masseter alone is not always sufficient in completely reducing or preventing bruxism. A study by Asutay et al (2017) used a dose of 20 units into each masseter muscle, using four points and 5 units per point. The procedure within this study used injections to the origin, insertion, anterior and posterior parts of the masseter muscle, which was identified by asking the patient to clench their jaw. In reality, it is reasonable to suggest that these are relatively large doses when compared to the standard dose used for the purpose of facial slimming only, which, as stated above, may only intend to weaken the muscle and not completely prevent action.
It is difficult to ascertain from the existing literature an average dose that is used in the treatment of bruxism using BoNTA, for the purpose of this article. This prompts the author to emphasise the need for thorough, practical training in any procedure, before it is undertaken - and the requirement for further research to be undertaken in relation to the appropriate doses required in the treatment of bruxism using BoNTA. Furthermore, it is important to approach treatments such as this with a degree of caution, and there are a number of things to consider before commencing this treatment.
First, it is absolutely crucial that the practitioner is fully familiar with the intricacies of the facial muscles. Any injector practising facial aesthetics (and specifically, injecting BoNTA) should be confident and competent in knowing where each muscle sits, as well as its role in the facial anatomy. In a treatment such as this, the author believes it is reasonable to suggest that the buccinator and risorius muscles could well be caught up in the effects of the drug, and this is something that must be considered. Peng and Peng (2018) commented on the need to inject ‘within the safe-zone’ of the masseter, ensuring that injections are ideally only in 3–4 different locations—at least 1 cm from any border—in order to support the prevention of complications.
The author believes that a conservative approach is reasonable in any treatment. Overdosing on product at the initial stages of treatment can result in unwanted effects further down the line. A step-by-step approach, and continuous progression of treatment, is incorporated into the personal practice of the author. The author finds that this has proven to produce continuously effective results, while reducing the risk of complications. More product can always be added, but cannot always be removed. Similarly, the author believes that patients can often respond very differently to treatment—there is rarely a ‘textbook’ response to treatment that can be applied to all patients. For example, in the case of BoNTA, the author has encountered many patients who require only small dosages to gain effective results, as well as many patients who typically require more product to gain an effective result. The conservative approach can often be considered alongside a holistic view, ensuring that each patient, and their expectations, are individually considered.
Suitable candidates for consideration
It is reasonable to suggest that a suitable candidate for consideration of treatment of bruxism using BoNTA is a patient who has tried other conservative options, such as mouth guards/mandibular splints, and is willing to adopt a multidisciplinary management approach. The practitioner must have a sound awareness of the alternative treatment options available, so that this can be discussed at the point of consultation. It may become clear during consultation that, while certain other options may not necessarily have been explored, they are still not a viable option for the patient. It is then for the medical practitioner to assess this and make a clinical judgement as to whether the patient is a suitable candidate—as with any other treatment.
It is this combined skillset of sound clinical knowledge and the ability to assess, consult and approach a patient holistically that sets medical practitioners apart from other practising injectors. Thus, these skills must play a part when selecting a suitable candidate for consideration and considering whether the patient's rationale for requesting treatment is justified. These considerations are secondary to the requirement for any patient being treated to be fit and well, and able to make rational and sober decisions regarding their treatment.
Research
Previously, studies have highlighted that there is not enough evidence to suggest that the use of BoNTA in the treatment of bruxism is effective. However, a retrospective study from Asutay et al (2017) highlighted that patients who failed to respond to conservative treatments, and thus underwent injections into the masseter muscle for clinically diagnosed nocturnal bruxism, reported significant differences in reduction of pain and bruxism activity following treatment (Asutay et al, 2017). This particular study concluded that BoNTA therapy could be promising and beneficial in the treatment of nocturnal bruxism when there has been no response to conservative treatment methods. The study identified several limiting factors that may prevent widespread use, such as high cost and the necessity for repeated injections.
The study of Tan and Jankovic (2000) concluded that, while there was a need for further research into the use of BoNTA on bruxism, when ‘administered by skilled practitioners, it is a safe and effective treatment for people with severe bruxism—particularly those with associated movement disorders' (Tan and Jankovic, 2000:215). The study reiterates that this treatment should only be considered for patients who have been unsuccessful in conservative therapy methods.
Key notices
It is important to note several key issues when considering offering this treatment. First, the use of BoNTA in the treatment of bruxism is considered ‘off-label’. British National Formulary (BNF) guidelines (2019a) list the indications for which the use of BoNTA is licensed. Charlson (2015) commented on the vast amount of cosmetic procedures that are carried out ‘off-label’ or ‘off-licence’ (using BoNTA, among other drugs), due to the positive effects and results they offer, and because of the often-limited product licences. With that said, it is imperative that the injector remains acutely aware that, on-or off-label, BoNTA remains a prescription-only medication and should only be prescribed using a gold-standard framework, such as that of the Royal Pharmaceutical Society (2016). It is also important to note that when any medication is used off-label, the patient being treated must be explicitly made aware of this prior to undergoing treatment.
Something to bear in mind is the classification of the procedure. Charlson (2015) described bruxism as a ‘cosmetic condition that can be treated with botulinum toxin.’ However, the author believes it is reasonable to suggest that treating true, severe bruxism would be better classed as a clinical, therapeutic procedure. It is reasonable to state that the administration of the BoNTA into the masseter for bruxism employs the same method as that of treating masseter hypertrophy (sometimes known as ‘jawline slimming—potentially a cosmetic procedure); however, indications and motives for treatment may be different, which is something that must be established during the initial consultation.
Contraindications, cautions and side effects
The treatment of bruxism using BoNTA must be approached in the same way as using BoNTA for any other treatment. As established, this means always using an evidence-based framework to support the prescribing process. Further to this, the treating practitioner must also be comfortable and competent in the knowledge regarding indications for treatment and whether the patient is a suitable candidate, as well as knowledge regarding contraindications, side effects and cautions of the treatment. A thorough awareness and understanding of the latter is important, not only as part of one's duty of care to the patient, but also, with a drug that can be used and constituted in so many ways, it is vital to be fully versed with the particular treatment for which you are using the drug. In the case of BoNTA and the indication for treatment, variables such as injection site, injection depth, product amount and product reconstitution must all be very well considered. Contraindications also vary, as some are specific only to certain indications for treatment, as per BNF guidance (2019a).
Other contraindications to BoNTA, as listed by Allergan (2019), include:
As stated, caution must always be taken in the event of off-label use. Similarly, it is important to be aware of any conditions that may cause undesired treatment results. These include:
It is also worth highlighting that, while voluntary movements such as biting are not usually affected by BoNTA in the masseter (American Academy of Facial Aesthetics, 2019); caution must be taken when selecting injection points in this area, due to the high risk of involving separate, undesired facial muscles. Peng (2018) highlighted that inappropriately located injections can lead to complications such as the loss of the full smile, an asymmetric smile or difficulty in opening the mouth. This is supported by Deschamps-Braly (2019) who also identified that other common problems associated with treating bruxism with BoNTA include difficulties with chewing and speaking, no noticeable reduction in symptoms following treatment, or reduction of symptoms in one masseter muscle but not the other.
It is reasonable to suggest that complications and side effects relating to this treatment can be caused by over-or under-dosing with product; diffusion of product into other muscles that reside nearby common injection points; misplaced injection points due to lack of anatomical knowledge or simply inadvertent injection of muscles that are not associated with preventing bruxism.
Duration of results and optimal time to retreat
Studies suggest that the effects of BoNTA can last anywhere between 3 and 6 months. With this in mind, Allergan (2019) stated that the duration of effect of BoNTA for glabellar lines is approximately 3–4 months, while highlighting that the safety and effectiveness of dosing with BoNTA more frequently than every 3 months has not been clinically evaluated. As such, patient expectations relating to treatment duration must be managed well and the treating practitioner must be mindful of the negative effects that over-promising the duration of results can have.
If taking a holistic approach, while it would be advisable to make the patient aware of the average duration of results (2-6 months) as part of the consulting and consenting process, the patient must be made aware that the duration of the effects can vary significantly between patients. It is also imperative that the practitioner advises their patient of the possibility that the treatment may not reduce or prevent bruxism, or its symptoms, at all.
Conclusion
While the use of BoNTA in the treatment of bruxism overall appears well tolerated and effective, it is vital to ensure that all other treatment options are considered before any treatment occurs. This is to ensure that patients are being treated holistically and are being supported by their practitioner to achieve the safest, most cost-effective result. It is imperative that any practitioner who does decide to offer bruxism treatment in their clinic is not only specifically trained to carry out the procedure (considering injection techniques, depths and doses), but also innately familiar with the facial anatomy and the side-effects that can occur due to inadequate anatomical knowledge. Appreciation and respect of BoNTA (indications, contraindications, cautions and side-effects) must also be adhered to by anyone who is using it in clinical practice, whether cosmetically or clinically.
Disclaimer
While this article is aimed at all registered and appropriately insured healthcare professionals undertaking facial aesthetics procedures for information purposes, it is important to note that anyone undertaking procedures to ease the effects of bruxism, using BoNTA, must be adequately trained, qualified and registered with the appropriate body.